Guard for presses and cther machinery



E. I. B. DANKS.

GUARD FOR PRESSES AND OTHER MACHINERY.

APPLICATION FILED SEPT. IG. I9I9.

Patented Nov. 9, 1920.

2 SHEETS-SHEET Il Pgj.

Avr/26% E. I. B. DANKS. GUARD FoR PRESSES AND OTHER MACHINERY.

APPLICATION FILED SEPT. I6. i919.

1,358,528. Patented Nov. 9, 1920.l

2 SHEETS-SHEET 2.

S'IA'I'ES` PATENT Gli'iFlE..

ELISHA JOHN BRYANT BANKS, F BIRIVIING-HAM, ENGLAND.

GUARD EUR PRESSES AND GTI-IER MACHINERY.

Specncatcn 'of Letters Patent.

Patented Nov. 9, i926.

Application le. September 16, 1919. Serial No. 324,120.

am. resin 'i :i l, l

"-elalica to automatic guards and other machinery, such uares l by the ram or other ble moving part y :lie machine.V

llfore particularly the invi :ion relates to guards of that type compi jing a sliding member arranged to move across the workspace.

'lhe

object of the present invention-is to Y l oftliis type which quickly l s protect position so as to fer the were space, soon as the tool has ionipleted onlva small part of its stroke, pri l' to the s.. l tool. reaching the proximity of 'the work.

According to the said invention there )vided in conjunction with the actuating mechanism, inea; s whereby, `on the sliding 1rd beiA tecting posi- "ace, a relative einher carried lie moving ,Y ne machine is pered while u moving part completes its stroke; and likewise, onV the guard being stopred in its wilrlidrarn position, a relative iiov nent of the operating member is permitted, while the moving part completes its return stroke.

Preferably the slide actuated by a lever or arm operated from the inov n0 part of the machine by rack-and-pinion o r equivalent gearing, in combination with a friction clutch which slips when the guard is arrested in its protecting position, but irrimediately acts 'to return the guard and quickly removes it from in front of the work-space when the moving part of the machine coniniences its return stroke, the clutch again slipping, on the guard reaching the withdrawn position, while the said inoving part completes its return stroke. 0

Figure 1 of the accompanying drawings s a front elevation of the guard as applied o a power press, the said guard being shown by full lines in its withdrawn position and by dotted lines in its protecting position.

Fig. 2 is a front elevation of the guard on a larger scale, and

Fig. is a vertical section showing the arrangement of the friction clutch.

The rana or plunger l of the press carries a toothed rack 2 gearingwith a pinion 3 mounted in a frame or bracket fl attached to the side standard Stof the press. "The pinion 8 engages with another pinion 6 fixed upon a spindle '7 carrying an integral collar or disk S forming onemeinber of a face-type friction clutch. The other member consists of a collar or disk 9 carried by a sleeve 10 freely mounted upon the spindle 7 and supported within a housinpi or'bearing 11 of the frame or bracket l. l e'tween the opposed faces of the collars or disks 8, 9 is interposed a washer 12 of ber, leather or the like, which is adapted to be gripped between the said parts, in order to convey the drive, by ineans of coiled. springs 13 located in recesses 14e in the sleeve 1 0. These springs bear at their outer ends against the face of the inner end 15 `of the guard-actuating lever lo. This lever is freely mounted upon c the spindle 'l' and carries two pins `17 (only one shown) engaging recesses in the end of the sleeve10, while interposed between the outer face of the end 15 ofthe lever and a metal washer 19keye`d to the spindlev 7 and lined by a nut v1S, is a fiber, leather or like washer 20. The parts 15, 20, 19 thus form a second friction clutch. rlChe lower end of the lever 16 is provided with a longitudinal slot 21 engaging a pin 22 carried by the guard 23, the latter being mounted to slide upon horizontal guide-rails 24, 25. The guard 28 may be made of sheet-metal., the lower edge being secured to a sleeve 26 sliding on the lower rail and adapted to engage with stop brackets 27, 2S, at opposite ends of the rails.

ln operation, as the ram of the press descends, the rack 2, acting through the pinions 3, 6, rotates the shaft 7, and through the medium of the friction clutches the lever or arm 16 is moved angularly in order to.

completes its stroke. As soon as the ram commences to rise, the motion is transmitted through the gearing and clutches in order quickly to return the guard to its withdrawn position clear of the work-space, the sleeveY 26A engagingthe stopebracket 27 to'arrest the movement of the guard. This happens soon after the tool has commenced its up stroke,

' in connection with a power-press, it is obvious that the guard is equally applicable to other machineryV having a reciprocating action. Y

'Y It is also evident that niodiiications may be made inV the illustrated embodiment or my invention Without departing from the spirit thereof, and `it is my'desire to include all such modifications within the purview of my invention if properly within the scope of the appended claims,

Having fully described by inventionIk what I desire to claim and secure by Letters Patent is I l. A guard for machinery comprising a sliding member which is actuated by a lever or arm operated from a movingpart ofthe machine, in combination with a friction device which slips when the guardis arrested in itsA protecting position after the said moving part has made only a portion ofV its stroke, but immediately acts to return the guard onthe moving part commencing its return stroke, the said friction device again the work space, of a lever for operating the sliding member, a shaft upon which the lever isv freely'mounted, means for driving the shaft from the machine, and a friction clutch between the shaft and operating lever,

said friction clutch comprising a sleeve vhaving a driving connectionwith the lever and forced axially against a friction surface interposed between the end of the sleeve and a collar on the shaft. Y Y

3; ln guards for machinery, the combina tion with a sliding member movable across the work-space, of a lever for operating the sliding member,a shaft upon which the lever is freely mounted, Ameans for driving the shaft fromV the machine,afriction clutch be* tween theouter faceof the lever andan abutment on the shaft, and a second friction clutch between the shaft and lever comprising a sleeve havinga driving connectionV with the'lever and forced'axiallyagainst a friction surface interposed between the end of the sleeve and a collar on the shaft.

In testimony whereof I have hereunto set myV hand in presence of two subscribing witnessesf ELESH JOHN BRYANT DANKS.

V1ilitnesses z C. H.;MnnRETT, H. O. PRATT. a 

